When working on a wellbore, the wellbore sometimes needs to be sealed for extended periods of time. The seal often needs to be maintained for an extended period of time to prevent injury to workers or an environmental release. In such a situation, packers can be deployed to seal the wellbore. A packer can seal the wellbore with an elastomer seal that extends radially outward from a cylindrical core to seal against the wall of a wellbore.